CVE-2026-7423
MEDIUMInteger Underflow in ICMP Echo Reply Processing in FreeRTOS-Plus-TCP
Title source: cnaDescription
Integer underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB. To mitigate this issue, users should upgrade to the fixed version when available.
References (4)
Core 4
Core References
Vendor Advisory vendor-advisory
https://aws.amazon.com/security/security-bulletins/2026-021-aws/
Third Party Advisory third-party-advisory
https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-7r59-2pgv-9v2r
Scores
CVSS v3
5.3
EPSS
0.0022
EPSS Percentile
12.5%
Attack Vector
ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-191
Status
published
Products (5)
amazon/freertos-plus-tcp
4.0.0 - 4.2.6
AWS/FreeRTOS-Plus-TCP
4.0.0 - 4.2.6
AWS/FreeRTOS-Plus-TCP
4.2.6
AWS/FreeRTOS-Plus-TCP
4.3.0 - 4.4.1
AWS/FreeRTOS-Plus-TCP
4.4.1
Published
Apr 29, 2026
Tracked Since
Apr 30, 2026